外键错误实体框架

Question

The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.

这个泛型错误很烦人，我怎么找出哪个外键失败了呢？

Answer 1

据我所知，实际的错误是表中的外键列没有接受null，并且条目没有提供该列的数据。如果您使用过fluent api，一种选择是将IsRequired()更改为IsOptional()以进行外键映射